Why iPhone 6 is being hanging after new update

This performance management works by looking at a combination of the device temperature, battery state of charge, and battery impedance. Only if these variables require it, iOS will dynamically manage the maximum performance of some system components, such as the CPU and GPU, in order to prevent unexpected shutdowns. As a result, the device workloads will self-balance, allowing a smoother distribution of system tasks, rather than larger, quick spikes of performance all at once. In some cases, a user may not notice any differences in daily device performance. The level of perceived change depends on how much performance management is required for a particular device.

In cases that require more extreme forms of this performance management, the user may notice effects such as:

• Longer app launch times
• Lower frame rates while scrolling
• Backlight dimming (which can be overridden in Control Center)
• Lower speaker volume by up to -3dB
• Gradual frame rate reductions in some apps
• During the most extreme cases, the camera flash will be disabled as visible in the camera UI
• Apps refreshing in background may require reloading upon launch

Many key areas are not impacted by this performance management feature. Some of these include:

• Cellular call quality and networking throughput performance
• Captured photo and video quality
• GPS performance
• Location accuracy
• Sensors like gyroscope, accelerometer, barometer
• Apple Pay